.flex {
    display: -webkit-box;
    display: -webkit-flex;
    display: -ms-flexbox;
    display: flex;
}

.flex-wrap {
    display: -webkit-box;
    display: -webkit-flex;
    display: -ms-flexbox;
    display: flex;

    -webkit-flex-wrap: wrap;
    -moz-flex-wrap: wrap;
    -ms-flex-wrap: wrap;
    -o-flex-wrap: wrap;
    flex-wrap: wrap;
}

/* 主轴为垂直方向 */
.flex-column {
    -webkit-box-orient: vertical;
    -webkit-flex-direction: column;
    -ms-flex-direction: column;
    flex-direction: column;
}

/* 主轴为水平方向  */
.flex-row {
    -webkit-box-orient: horizontal;
    -webkit-flex-direction: row;
    -ms-flex-direction: row;
    flex-direction: row;
}

/* 交叉轴上顶端对齐 */
.flex-align-start {
    -webkit-align-items: flex-start;
    -webkit-box-align: start;
    -ms-flex-align: start;
    align-items: flex-start;
}

/* 交叉轴上居中对齐 */
.flex-align-center {
    -webkit-align-items: center;
    -webkit-box-align: center;
    -ms-flex-align: center;
    align-items: center;
}

/* 交叉轴上底端对齐 */
.flex-align-end {
    -webkit-align-items: flex-end;
    -webkit-box-align: end;
    -ms-flex-align: end;
    align-items: flex-end;
}

/* 主轴上顶端对齐 */
.flex-pack-start {
    -webkit-box-pack: start;
    -webkit-justify-content: flex-start;
    -ms-flex-pack: start;
    justify-content: flex-start;
}

/* 主轴上居中 */
.flex-pack-center {
    -webkit-box-pack: center;
    -webkit-justify-content: center;
    -ms-flex-pack: center;
    justify-content: center;
}

/* 主轴上两端对齐 */
.flex-pack-justify {
    -webkit-box-pack: justify;
    -webkit-justify-content: space-between;
    -ms-flex-pack: justify;
    justify-content: space-between;
}

/* 主轴上底端对齐 */
/* 右对齐 */
.flex-pack-end {
    -webkit-box-pack: end;
    -webkit-justify-content: flex-end;
    -ms-flex-pack: end;
    justify-content: flex-end;
}

.flex-1 {
    -webkit-box-flex: 1;
    -webkit-flex: 1;
    -ms-flex: 1;
    flex: 1;
}

.flex-2 {
    -webkit-box-flex: 2;
    -webkit-flex: 2;
    -ms-flex: 2;
    flex: 2;
}

.flex-3 {
    -webkit-box-flex: 3;
    -webkit-flex: 3;
    -ms-flex: 3;
    flex: 3;
}

/*
 * flex布局样式说明
 * @example :  flex-row-justify-center
 * 四个单词依次为：flex布局 、  主轴方向（水平或者垂直）、  主轴上的对齐方式 、 交叉轴上的对齐方式
 */
.flex-row-justify-start {
    display: -webkit-box;
    display: -webkit-flex;
    display: -ms-flexbox;
    display: flex;

    -webkit-box-orient: horizontal;
    -webkit-flex-direction: row;
    -ms-flex-direction: row;
    flex-direction: row;

    -webkit-box-pack: justify;
    -webkit-justify-content: space-between;
    -ms-flex-pack: justify;
    justify-content: space-between;

    -webkit-align-items: flex-start;
    -webkit-box-align: start;
    -ms-flex-align: start;
    align-items: flex-start;
}

.flex-row-justify-center {
    display: -webkit-box;
    display: -webkit-flex;
    display: -ms-flexbox;
    display: flex;

    -webkit-box-orient: horizontal;
    -webkit-flex-direction: row;
    -ms-flex-direction: row;
    flex-direction: row;

    -webkit-box-pack: justify;
    -webkit-justify-content: space-between;
    -ms-flex-pack: justify;
    justify-content: space-between;

    -webkit-align-items: center;
    -webkit-box-align: center;
    -ms-flex-align: center;
    align-items: center;
}

.flex-row-justify-end {
    display: -webkit-box;
    display: -webkit-flex;
    display: -ms-flexbox;
    display: flex;

    -webkit-box-orient: horizontal;
    -webkit-flex-direction: row;
    -ms-flex-direction: row;
    flex-direction: row;

    -webkit-box-pack: justify;
    -webkit-justify-content: space-between;
    -ms-flex-pack: justify;
    justify-content: space-between;

    -webkit-align-items: flex-end;
    -webkit-box-align: end;
    -ms-flex-align: end;
    align-items: flex-end;
}

.flex-row-start-end {
    display: -webkit-box;
    display: -webkit-flex;
    display: -ms-flexbox;
    display: flex;

    -webkit-box-orient: horizontal;
    -webkit-flex-direction: row;
    -ms-flex-direction: row;
    flex-direction: row;

    -webkit-box-pack: start;
    -webkit-justify-content: flex-start;
    -ms-flex-pack: start;
    justify-content: flex-start;

    -webkit-align-items: flex-end;
    -webkit-box-align: end;
    -ms-flex-align: end;
    align-items: flex-end;
}

.flex-row-start-center {
    display: -webkit-box;
    display: -webkit-flex;
    display: -ms-flexbox;
    display: flex;

    -webkit-box-orient: horizontal;
    -webkit-flex-direction: row;
    -ms-flex-direction: row;
    flex-direction: row;

    -webkit-box-pack: start;
    -webkit-justify-content: flex-start;
    -ms-flex-pack: start;
    justify-content: flex-start;

    -webkit-align-items: center;
    -webkit-box-align: center;
    -ms-flex-align: center;
    align-items: center;
}

.flex-row-end-center {
    display: -webkit-box;
    display: -webkit-flex;
    display: -ms-flexbox;
    display: flex;

    -webkit-box-orient: horizontal;
    -webkit-flex-direction: row;
    -ms-flex-direction: row;
    flex-direction: row;

    -webkit-box-pack: end;
    -webkit-justify-content: flex-end;
    -ms-flex-pack: end;
    justify-content: flex-end;

    -webkit-align-items: center;
    -webkit-box-align: center;
    -ms-flex-align: center;
    align-items: center;
}

.flex-row-center-center {
    display: -webkit-box;
    display: -webkit-flex;
    display: -ms-flexbox;
    display: flex;

    -webkit-box-orient: horizontal;
    -webkit-flex-direction: row;
    -ms-flex-direction: row;
    flex-direction: row;

    -webkit-box-pack: center;
    -webkit-justify-content: center;
    -ms-flex-pack: center;
    justify-content: center;

    -webkit-align-items: center;
    -webkit-box-align: center;
    -ms-flex-align: center;
    align-items: center;
}

.flex-row-center-start {
    display: -webkit-box;
    display: -webkit-flex;
    display: -ms-flexbox;
    display: flex;

    -webkit-box-orient: horizontal;
    -webkit-flex-direction: row;
    -ms-flex-direction: row;
    flex-direction: row;

    -webkit-box-pack: center;
    -webkit-justify-content: center;
    -ms-flex-pack: center;
    justify-content: center;

    -webkit-align-items: flex-start;
    -webkit-box-align: start;
    -ms-flex-align: start;
    align-items: flex-start;
}

.flex-row-center-end {
    display: -webkit-box;
    display: -webkit-flex;
    display: -ms-flexbox;
    display: flex;

    -webkit-box-orient: horizontal;
    -webkit-flex-direction: row;
    -ms-flex-direction: row;
    flex-direction: row;

    -webkit-box-pack: center;
    -webkit-justify-content: center;
    -ms-flex-pack: center;
    justify-content: center;

    -webkit-align-items: flex-end;
    -webkit-box-align: end;
    -ms-flex-align: end;
    align-items: flex-end;
}

.flex-column-start-center {
    display: -webkit-box;
    display: -webkit-flex;
    display: -ms-flexbox;
    display: flex;

    -webkit-box-orient: vertical;
    -webkit-flex-direction: column;
    -ms-flex-direction: column;
    flex-direction: column;

    -webkit-box-pack: start;
    -webkit-justify-content: flex-start;
    -ms-flex-pack: start;
    justify-content: flex-start;

    -webkit-align-items: center;
    -webkit-box-align: center;
    -ms-flex-align: center;
    align-items: center;
}

.flex-column-center-center {
    display: -webkit-box;
    display: -webkit-flex;
    display: -ms-flexbox;
    display: flex;

    -webkit-box-orient: vertical;
    -webkit-flex-direction: column;
    -ms-flex-direction: column;
    flex-direction: column;

    -webkit-box-pack: center;
    -webkit-justify-content: center;
    -ms-flex-pack: center;
    justify-content: center;

    -webkit-align-items: center;
    -webkit-box-align: center;
    -ms-flex-align: center;
    align-items: center;
}

.flex-column-center-start {
    display: -webkit-box;
    display: -webkit-flex;
    display: -ms-flexbox;
    display: flex;

    -webkit-box-orient: vertical;
    -webkit-flex-direction: column;
    -ms-flex-direction: column;
    flex-direction: column;

    -webkit-box-pack: center;
    -webkit-justify-content: center;
    -ms-flex-pack: center;
    justify-content: center;

    -webkit-align-items: flex-start;
    -webkit-box-align: start;
    -ms-flex-align: start;
    align-items: flex-start;
}

.flex-column-end-center {
    display: -webkit-box;
    display: -webkit-flex;
    display: -ms-flexbox;
    display: flex;

    -webkit-box-orient: vertical;
    -webkit-flex-direction: column;
    -ms-flex-direction: column;
    flex-direction: column;

    -webkit-box-pack: end;
    -webkit-justify-content: flex-end;
    -ms-flex-pack: end;
    justify-content: flex-end;

    -webkit-align-items: center;
    -webkit-box-align: center;
    -ms-flex-align: center;
    align-items: center;
}